Recently, there have been proposed many image processing methods for improving degradation in image quality (restoring the image quality) when an image of an object captured by a camera or the like is degraded to allow the object to be favorably perceived.
In, this regard, conventional techniques are disclosed in Patent Document 1 and Patent Document 2 (referred to as Conventional Technique 1 and Conventional Technique 2). Conventional Technique 1 discloses a fluctuation noise reduction processing method in which image deterioration such as blur of an image is small by extracting fluctuation components present in continuous images in time series as motion vectors between images, tracking the motion vectors to obtain a center of fluctuation, and rearranging partial images or pixels becoming a starting point of the fluctuation in the center position. Further, Conventional Technique 2 discloses a technique of correcting distortion of an image due to fluctuation of a monitoring camera in real time, and identifying a moving object of interest in the moving image online. Further, the inventors of the present patent application have filed, as Japanese Patent Application No. 2010-253727 (Japanese Patent Application Publication No. 2012-104018) (Conventional Technique 3), a technique for improving the quality of an image by calculating optical flow for input images and a reference image which is a time average of the input images, calculating local fluctuations (motion vectors) of the input images, and moving partial images of the input images so as to cancel the heat haze fluctuation using the motion vectors.
Patent Document 1: Japanese Patent Application Publication No. H3-95686
Patent Document 2: Japanese Patent No. 4040651
According to Conventional Techniques 1 to 3, in a case where the quality of an image is degraded due to camera shake, heat haze or the like when the image is captured by a camera, it is possible to improve the image quality degradation of a background object and obtain a favorable image. However, there is a problem that it is impossible to correct the fluctuation of the heat haze on a moving object.